Air Conditioning - condensor fan does not turn on

Hello all,
I have central air and heat (heat pump). When the thermostat kicks on the outside unit, the fan does not turn on. It sounds like the compressor is turning on, but it might be struggling (sounds a little like it might be straining). The breakers do not pop and the inside blower is working well. I did not feel and warm air out of the ducts, but I did not keep it on very long in fear of burning something up. The outside fan rotates smoothly and freely when turned by hand.
Any ideas as to what the problem is? Any tips would be much appreciated!
Thanks,
John

The most likely cause is a bad motor or capacitor. There are other less likely possibilities especially with heat pumps.

You have a lot of ifs ifs here. First when it calls for heat if you give the fan a push will it run???? If so it can just be the capacitor. If not can be the defrost board . Lots of units now the fan dont run in the defrost mode. Then like Jim said can be the motor. Try the AC and see if the fan runs. Till you get it fixed go to EME or AUX for heat. ;)

Thanks Jim and Ed,
It could be the fan motor I suppose. The sun is shining today and it is warming up a bit, so I'll go out and pull the housing off and look at things.
I tried the cooling mode and it did not turn the fan on either. I'll ohm out the capacitor and the motor. I've been an electronic technician for over 25 years so I know my way around that stuff. I'm just hoping it's not the compressor (sp).
I'm not sure about the "defrost mode", but it is well above freezing here. Thanks for reminding me about the EME and AUX mode. Logic says that doesn't use the outside condensor unit.
Much Thanks Again,
John

I just tried it again in the heat mode and the outside fan turned ON as normal. It seems OK for now. Might this be an intermitten issue or did I give it enough time to reset itself? I'll keep an eye on it to see either way. I'd rather fix it myself than spend a lot of money. I just found this forum and I think it's great.
Thanks for all your help!!!
John

if the capacitors check out, and the fan spins freely(not a bearing issue) then theres a good chance the fan relay in the defrost board is faulty. check to be sure your getting the correct voltage in/out of the defrost board to the fan

I really appreciate all your replies. I'll try and hunt down a schematic of the unit for future reference. So far the thing is working as advertized. I will most definetly keep in mind the advice y'all gave for future problems. I really can't thank you enough!!!!!
But.... Thanks again,
John